Additive and subtractive manufacturing technologies enable computer designs, such as CAD files, to be made into 3D objects. 3D printing, also known as additive manufacturing, typically comprises depositing, curing, fusing, or otherwise forming a material into sequential cross-sectional layers of the 3D object. For example, fused deposition modeling techniques, which are generally disclosed in U.S. Pat. No. 4,749,347 and U.S. Pat. No. 5,121,329, among others, which are incorporated by reference herein in their entirety, include melting a filament of build material and extruding the print material out of a dispenser that is moved in the x-, y-, and z-axes relative to a print pad. The print material is generally deposited in layers in the x- and y-axes to form cross-sectional layers that are stacked along the z-axis to form the 3D object.
3D objects that do not have a planar down-facing surface typically must be supported in some or all areas below the 3D objects. In addition, some additive manufacturing techniques cannot print a 3D object directly onto the print pad because such direct contact between the printed object and the print pad can cause surface flaws on the contacting surface of the printed object or may cause difficulty in the separation of the printed object from the print pad.
Certain 3D printing technologies overcome these problems by printing a support structure between the printed 3D object and the print pad. With regards to fused deposition modeling, one technique is using two separate print materials. A first print material, sometimes called a build material, is used to print the printed 3D object and the second print material, sometimes called a support material, is used to support the printed 3D object. Once a print process is complete, the printed 3D object may be mechanically removed from the support structure because of the lack of bonding at the interface between the build material and the support material, the support material may be heated and melted away from the printed 3D object, or the support material may be dissolved away from the printed 3D object. A second technique used with fused deposition modeling to support the printed object, that is most often used with systems that dispense only a singled print material, is to print a support structure under the printed 3D object and then mechanically remove the support structure after the print operation is complete. The upper portion of the support structure that contacts the down-facing surface of the printed 3D object is typically a long bead of material deposited from the dispenser, which may be difficult to remove without scarring or otherwise impairing the quality of the down-facing surface. Therefore, a need exists to provide support structures that adequately support the printed 3D object and that are easy to remove without damaging the printed object.
Therefore, a need exists to improve the printing of 3D objects to provide accurate parts, models, and other 3D objects that are adequately supported during the print process by supports that may be easily removed.